Sublimation study of anhydrous ferric chloride

Abstract

Steady-state sublimation vapour pressures of anhydrous ferric chloride have been measured by the continuous gravimetric Knudsen-effusion method from T = 383.9 K to 445.2 K. Based on a correlation of Δ cr g H m ∘ ( 298.15 K ) and Δ cr g S m ∘ ( 298.15 K ) , a recommended p( T) equation has been obtained for FeCl 3(cr): lg ( p/Pa) = 1.895 · lg ( T/K) − 3.047 · 10 −3( T/K) − 3.672 · 10 −7( T/K) 2 − 7.321 · 10 3(K/ T) + 14.017. Condensation coefficients and their temperature dependence have been derived from the effusion measurements.